Water pump for vehicle

ABSTRACT

Provided is an automotive water pump in which regions of a rotor chamber and a driver chamber are formed and a stator and a connector are implemented into an integral pump body by an insert molding method, to thus enhance a waterproof performance of the water pump and enhance an assembly through simplification of an assembly structure. The automotive water pump includes: a pump body in which a stator and a connector are molded in an integral structure, and a partial structure of an upper-end rotor chamber and a lower-end driver chamber is independently formed; a rotating assembly that is accommodated and combined in the rotor chamber, and that pressurizes and discharges a coolant that flows in from the outside by rotation of an impeller that is combined on top of a rotating axis according to rotation of the rotating axis to which a rotor facing the stator is fixed; and a driver cover that covers the driver chamber combined with a driver including the connector.

TECHNICAL FIELD

The present invention relates to an automotive water pump, and more particularly, to an automotive water pump in which regions of a rotor chamber and a driver chamber are formed and a stator and a connector are implemented into an integral pump body by an insert molding method, to thus enhance a waterproof performance of the water pump and enhance an assembly through simplification of an assembly structure.

Also, the present invention relates to an automotive water pump in which the water pump is directly coupled with an engine block according to a case where a pump cover is combined with a pump body, or a case where the pump cover is not combined with the pump body.

BACKGROUND ART

An engine that is powered by combustion of fuels gets to a high temperature due to the temperature of combustion gases that are burnt within a cylinder, and thus essentially requires cooling in order to protect peripheral components of a combustion chamber included in the engine. For this purpose, an automobile car is equipped with a water pump, to thus circulate cooling water as a coolant so that the engine is maintained at a proper temperature. In other words, a water jacket is formed to allow a coolant to pass through a cylinder block and a cylinder head that are included in an engine for an automobile car, and a water pump for pumping a coolant to the water jacket is provided on one side of the front of the engine. Here, a radiator is formed in front of the water pump, to cool the coolant heated by the engine, and coolant hoses for the inflow and outflow of the coolant are connected between the radiator and the water jacket.

Hereinafter, a process of circulating a coolant by a water pump will be briefly described. The coolant that flows out by the water pump is introduced into a water jacket that is provided in a cylinder block and a cylinder head of a high temperature, and is heated through a heat-exchange between the coolant and the high temperature cylinder block and head. Then, the heated coolant undergoes a heat dissipation process in a radiator, to then flow in the water pump. Such a coolant circulating process is repeated.

Meanwhile, the water pump is classified into a mechanical pump that receives a driving force of an engine via a belt or chain and thus is driven, and an electronic pump that is rotated by driving of a motor.

First, the mechanical water pump is connected to a pulley fixed to a crankshaft of the engine and is driven depending on rotation of the crankshaft, that is, rotation of the engine. In this case, a flow rate of a coolant that flows out from a mechanical water pump is determined depending on the rotational speed of the engine. Meanwhile, a flow rate of a coolant that is required for a heater and a radiator is constant regardless of the rotational speed of the engine. As a result, it is not only difficult to normally operate the heater and the radiator at a small number of engine revolutions, but the number of engine revolutions should be also heightened in order to normally operate the heater and the radiator, to thus reduce fuel-efficiency of an automobile car.

Next, the electronic water pump is driven by rotation of the motor that is controlled by a control device. In other words, since the electronic water pump can determine a flow rate of the coolant regardless of the rotational speed of the engine, the electronic water pump is recently spotlighted compared to the mechanical water pump.

However, since the electronic water pump uses a pump motor is operated by electricity, there is a need to develop a variety of technologies enough to secure performance of waterproof, to thereby improve performance and increase durability.

For this purpose, a conventional electronic water pump uses a mechanical seal for sealing a pump motor in order to prevent bearing failure and shortening of the life span of belts, due to the external drainage of water inside the water pump or coolant leak. This requires a post-process of mounting a separate mechanical seal in a water pump, to thus cause a prime cost rising factor of a motor due to the rise of a processing cost and a material cost.

In addition, in the case of a conventional electronic water pump, a mechanical seal is deleted therefrom, and a canned cover is inserted thereinto, to thereby form a box on the edge of a rotor of a motor and to thus seal the rotor of the motor to then be submerged into a fluid. This may prevent water from leaking from the rotor to the stator of the motor to some extent, but a canned cover should be separately manufactured and thus the motor should be assembled, to accordingly cause a prime cost to rise up and assembly productivity to decline. Moreover, in the case that a canned cover is applied, an alternative proposal has not been made with respect to a waterproof structure against water introduced from an external water source to the stator.

Moreover, the electronic water pump is configured to have a rotor chamber, a stator chamber, and a driver chamber of a pump body, respectively, on a dual basis. In other words, a drive case is combined with the pump body, and then a driver cover is assembled with a driver case, to thereby implement the rotor chamber, the stator chamber, and the driver chamber, respectively.

As described above, a series of conventional assembly processes such as a coupling of the rotor of the motor with the stator thereof, an assembling of the canned cover, and a coupling of the driver case with the driver cover are sequentially performed, which makes, the structure of the water pump and the assembly process complicated. This eventually leads to a rise of production costs of the water pump and a decrease in productivity.

In addition, the conventional water pump requires coolant hoses for the inflow and outflow of the coolant between the radiator and water jacket, and thus the coolant hoses need to be replaced at the time of occurrence of the coolant hoses damaged due to vibration or impact according to driving of an automobile car.

Thus, as described above, since a canned cover should be separately provided in a conventional water pump to form a waterproof structure, there is a problem that productivity is lowered. Also, since a rotor chamber, a stator chamber, and a driver chamber of a pump body, respectively, are configured on a dual basis, there is a problem that an assembly structure is complicated.

DISCLOSURE Technical Problem

To solve the above problems or defects, it is an object of the present invention to provide an automotive water pump in which regions of a rotor chamber and a driver chamber are formed and a stator and a connector are implemented into an integral pump body by an insert molding method, to thus enhance a waterproof performance of the water pump and enhance an assembly through simplification of an assembly structure.

The object of the present invention is not limited to the above-described object, and other objects and advantages of the present invention can be appreciated by the following description and will be understood more clearly by embodiments of the present invention. In addition, it will be appreciated that the objects and advantages of the present invention will be easily realized by means shown in the appended patent claims, and combinations thereof.

Technical Solution

To accomplish the above and other objects of the present invention, according to an aspect of the present invention, there is provided an automotive water pump comprising:

-   -   a pump body in which a stator and a connector are molded in an         integral structure, and a space for a rotor chamber and a space         for a driver chamber are provided on top and bottom portions of         the pump body, respectively;     -   a rotating assembly that is accommodated and combined in the         rotor chamber, and that pressurizes and discharges a coolant         that flows in from the outside by rotation of an impeller that         is combined on top of a rotating axis according to rotation of         the rotating axis to which a rotor is fixed; and     -   a driver cover that covers the driver chamber.

Preferably but not necessarily, the automotive water pump further comprises a pump cover that comprises a volute chamber that is directly coupled to the pump body to thus guide a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.

Preferably but not necessarily, the pump cover is inserted into the inside of an engine block.

Preferably but not necessarily, the engine block comprises the volute chamber that is directly coupled to the pump body to thus guide a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.

Preferably but not necessarily, the pump body is molded by using a single material of polyphenylene sulfide (PPS) or bulk molding compound (BMC), with an insert molding method.

Preferably but not necessarily, the rotor primarily fixes a back yoke and a permanent magnet by a rotor cover, and then secondarily surrounds and fixes the back yoke and an outer circumferential surface of the back yoke by insert molding the BMC.

Preferably but not necessarily, bearings are inserted into and combined with top and bottom portions of the rotating assembly when the rotating assembly are coupled with the rotor chamber.

According to another aspect of the present invention, there is provided an automotive water pump comprising:

-   -   a pump body in which a stator and a connector are molded in an         integral structure, and a partial structure of an upper-end         rotor chamber and a lower-end driver chamber is independently         formed;     -   a rotating assembly that is accommodated and combined in the         rotor chamber, and that pressurizes and discharges a coolant         that flows in from the outside by rotation of an impeller that         is combined on top of a rotating axis according to rotation of         the rotating axis to which a rotor facing the stator is fixed;         and     -   a driver cover that covers the driver chamber combined with a         driver including the connector.

Preferably but not necessarily, the automotive water pump further comprises a pump cover that comprises a volute chamber that is directly coupled to the pump body to thus guide a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.

Preferably but not necessarily, the stator core comprises a fastening hole passing through a portion of the stator core exposed to the outside of the pump body, to thus be coupled directly to the engine block.

Preferably but not necessarily, the stator core comprises a fastening hole passing through a portion of the stator core exposed to the outside of the pump body, to thus be coupled directly to the engine block, and the engine block comprises the volute chamber that guides a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.

Preferably but not necessarily, the pump body is molded by using a single material of polyphenylene sulfide (PPS) or bulk molding compound (BMC), with an insert molding method.

Preferably but not necessarily, the stator core comprises through-holes or outer circumferential grooves into which a molding material of polyphenylene sulfide (PPS) or bulk molding compound (BMC) is filled at the time of performing an insert molding method, to then be fixed to the pump body.

Preferably but not necessarily, the rotor primarily fixes a back yoke and a permanent magnet by a rotor cover, and then secondarily surrounds and fixes the back yoke and an outer circumferential surface of the back yoke by insert molding the BMC.

Preferably but not necessarily, bearings are inserted into and combined with top and bottom portions of the rotating assembly when the rotating assembly are coupled with the rotor chamber.

Advantageous Effects

As described above, an automotive water pump according to the present invention provides an effect of enhancing a waterproof performance of the water pump and enhancing an assembly through simplification of an assembly structure in which regions of a rotor chamber and a driver chamber are formed and a stator and a connector are implemented into an integral pump body by an insert molding method.

In addition, according to the present invention, a water pump is manufactured without inserting a separate canned cover by providing a rotor chamber corresponding to a canned structure as a pump body, to thereby provide an effect of reducing a cost increasing factor due to a rise in a processing cost and a material cost.

Furthermore, according to the present invention, a stator is externally extended, to thus maximize a heat dissipation effect, and a stable support structure is simultaneously established in order to be mounted with an engine block to thereby promote improvement of assembly.

In addition, according to the present invention, a water pump is directly combined with an engine block, to thus have an effect of circulating a coolant without having any coolant hoses.

DESCRIPTION OF DRAWINGS

FIG. 1A is a cross-sectional view of a water pump employing a waterproof structure according to a first embodiment of the present invention.

FIG. 1B is a decomposition cross-sectional view of the water pump of FIG. 1A.

FIG. 1C is a plan view of a pump body in the water pump of FIG. 1A.

FIG. 2A is a cross-sectional view of a water pump employing a waterproof structure according to a modified embodiment of the first embodiment of the present invention.

FIG. 2B is a plan view of a pump body in the water pump of FIG. 2A.

FIG. 3A is a cross-sectional view of a water pump employing a waterproof structure according to a second embodiment of the present invention.

FIG. 3B is a plan view of a pump body in the water pump of FIG. 3A.

FIG. 4A is a cross-sectional view of a water pump employing a waterproof structure according to a modified embodiment of the second embodiment of the present invention.

FIG. 4B is a plan view of a pump body in the water pump of FIG. 4A.

BEST MODE

Aforementioned objects, features and advantages will become clearer through a detailed description which is described below in detail with reference to the accompanying drawings. Accordingly, one of ordinary skill in the art can easily carry out technical spirit of the present invention. In the description of the present invention, if it is determined that a detailed description of commonly-used technologies or structures related to the invention may unnecessarily or unintentionally obscure the subject matter of the invention, the detailed description will be omitted. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying FIGS. 1A to 4B.

FIG. 1A is a cross-sectional view of a water pump employing a waterproof structure according to a first embodiment of the present invention. FIG. 1B is a decomposition cross-sectional view of the water pump of FIG. 1A. FIG. 1C is a plan view of a pump body in the water pump of FIG. 1A. FIGS. 1A and 1B are cross-sectional views taken along line A-A′ of FIG. 1C.

Referring to FIGS. 1A to 1C, a water pump employing a waterproof structure according to a first embodiment of the present invention, includes a pump body 110, a pump cover 120, a driver cover 130, a stator 140, a rotor 150, a rotating assembly 160, and a driver 170.

The water pump according to the first embodiment has a waterproof structure in which a canned cover is not basically inserted, and is molded in an integral structure into the pump body 110 of a single material (for example, polyphenylene sulfide (PPS), bulk molding compound (BMC) and the like) through an insert molding method. In this case, the water pump is configured so that the pump cover 120 is not only directly coupled to the pump body 110 made of a single material, but an engine block 180 is also directly coupled to the pump body 110 without passing through a predetermined connecting tube. Here, polyphenylene sulfide (PPS) is a kind of a thermoplastic resin, and has heat resistance, chemical resistance, flame resistance, and excellent electrical properties, and mineral affinity.

Hereinbelow, each component of the water pump according to the first embodiment will be described in detail.

The pump body 110 has a top and bottom open structure, but regions formed at the top and bottom of the pump body 110 are independent spaces without penetrating through each other, and form part of a rotor chamber (RC) and a driver chamber (DC), respectively. Here, the pump body 110 does not form a series of a stator chamber, the rotor chamber (RC) and the driver chamber (DC), by combining a driver case at the bottom of the pump body 110 as an additional work and then assembling a driver cover with the pump body 110, but forms some structures for configuration of chambers in an integral form, as a result of a molding process of a single material and a single configuration as described above. In other words, the pump body 110 is integrally molded with the stator 140 through an insert molding method, in the case of the stator chamber, and forms some structures for configuration of a rotor chamber (RC) at a top opening portion in the case of the rotor chamber (RC), and forms some structures for configuration of a driver chamber (DC) at a bottom opening portion in the case of the driver chamber (DC).

Here, the rotor chamber RC and the driver chamber DC are formed in an independent space, respectively, on the top and bottom portions of the pump body 110. Accordingly, even though a coolant is introduced into the rotor chamber RC, the driver chamber DC is guaranteed to have a shielding function so that the coolant does not leak from the rotor chamber RC. In particular, even if a canned cover is not inserted, the rotor chamber RC is formed to have a box on an outer edge of the rotor 150, as a result of molding the pump body 110, to thereby form a structure corresponding to the canned cover that can seal the rotor 150 so as to be immersed in the coolant.

In addition, the rotor chamber RC accommodates a rotating assembly 160 to which the rotor 150 is fixed, and the driver chamber DC accommodates a printed circuit board (PCB) 172 of a driver 170. In particular, the pump body 110 is molded with a connector 171 of the driver 170 in an integral structure through an insert molding method. Here, the PCB 172 is connected to the connector 171 through a connector pin 171 a.

Meanwhile, the pump body 110 is combined with a pump cover 120 on the top portion of the pump body 110 after the rotating assembly 160 to which the rotor 150 has been fixed has been accommodated in the rotor chamber RC. For example, the pump body 110 is combined with the pump cover 120 using a screw or bolt 113 a. A through-hole is formed on the pump body 110 and the pump cover 120, respectively, in order to couple the pump body 110 and the pump cover 120 with each other. In this case, a first O-ring groove 114 a of a trench structure is formed in the pump body 110 in order to place a first O-ring 114 for sealing between the pump body 110 and the pump cover 120.

In addition, the pump body 110 that has been combined with the pump cover 120 is combined with the engine block 180. For this purpose, as shown in FIG. 1C, the pump body 110 is formed to have a flange of a rectangular shape extending to the side surfaces on which the engine block 180 is combined. Metal stud nuts 113 c are integrally formed at corners of the rectangular flange of the pump body 110, respectively, in order to achieve a strong coupling with the engine block 180. The pump body 110 is combined with the engine block 180 by fastening screws or bolts 113 b with the stud nuts.

In addition, the pump body 110 is combined with a driver cover 130 on the bottom portion of the pump body 110 after the printed circuit board (PCB) 172 of the driver 170 has been accommodated in the driver chamber DC. For example, the pump body 110 is combined with the driver cover 130 using a screw or bolt 113 d. In this case, extension portions 115 a and 115 b are respectively formed in the pump body 110 and the driver cover 130, in order to form through-holes for coupling the pump body 110 and the driver cover 130 with each other.

In addition, a second O-ring groove 116 a of a trench structure is formed in the pump body 110 in order to place a second O-ring 116 for sealing between the pump body 110 and the driver cover 130.

The pump cover 120 is in charge of a function of a path through which a coolant flows, to thereby guide a flow of the coolant from the engine to a radiator. For this purpose, a pump cover inlet 121 connected to the engine and a pump cover outlet 122 connected to the radiator are extended to a predetermined length, respectively. Here, the pump cover 120 is formed to have the pump cover inlet 121 connected to the engine on the top portion of the pump cover 120, to thus make the coolant introduced from the engine, and to have the pump cover outlet 122 connected to the radiator on the side portion of the pump cover 120, to thus make the coolant pressurized by rotation of an impeller 162 discharged to the radiator. In this case, the pump cover 120 is formed to have the pump cover outlet 122 whose opening is narrower than that of the pump cover inlet 121, to thus pressurize the coolant and to thereby improve a heat dissipation effect.

In addition, the pump cover 120 is formed to have a coolant circulating path through a coupling with the pump body 110, and to have a volute chamber VC that pressurizes the coolant by rotation of the impeller 162 inside the pump cover 120.

The driver cover 130 is coupled to a bottom opening portion of the pump body 110. In this case, the driver cover 130 is coupled closely to the pump body 110, after a second O-ring 116 is inserted into a second O-ring groove 116 a that is protrudingly formed on a surface on which the pump body 110 is combined. Here, the driver cover 130 is preferably made of an aluminum material in order to externally dissipate heat generated from the driver 170.

The stator 140 is built in the pump body 110 and then is integrally molded. Accordingly, the stator 140 is not only mounted in a separate stator chamber, but is also guaranteed to have a shielding function against a leakage of the coolant. In this case, the stator 140 includes a stator core 141, a bobbin 142, and a coil 143.

The stator 140 is formed through processes of: combining a stator core 141 formed of a plurality of laminated thin films made of a magnetic material with a bobbin 142 made of an insulating resin and then winding a coil 143 on an outer circumference of the bobbin 142. Here, the bobbin 142 may be achieved into a structure that upper and lower bobbins are combined with each other, or may be integrally formed on an outer circumferential surface thereof by insert molding the stator core 141.

Here, although it is not shown in the drawings, the stator 140 is molded when the stator 140 is housed and integrally formed in the pump body 110, together with a connection line to the PCB 172 for applying drive signals to a Hall sensor substrate for detecting position of the rotor 150 and the coil 143, respectively.

The rotor 150 includes a back yoke 151, permanent magnets 152, rotor covers 153, and a rotor case 154. In this case, the rotor 150 is formed to have a number of N-pole and S-pole permanent magnets 152 that are alternately mounted on an outer circumferential surface of the back yoke 151 fixed to a rotating shaft 151. In this case, a plurality of grooves (not shown) are formed lengthily on the outer circumferential surface of the back yoke 151, and thus the permanent magnets 152 are inserted and mounted into the grooves (not shown).

In addition, the rotor covers 153 are provided to pressurize the top and bottom portions of the back yoke 151 and the permanent magnets 152, to thus primarily fix the back yoke 151 and the permanent magnets 152, at a state where the permanent magnets 152 have been inserted into the back yoke 151. In this case, the rotor covers 153 are made of copper or stainless steel whose specific gravity is large, and are made considering a function of a balance weight to balance the external forces exerted by rotation of the rotor 150. In addition, the rotor case 154 surrounds the outer circumferential surfaces of the permanent magnets 152, to thus secondarily fix the back yoke 151 and the permanent magnets 152, at a state where the rotor covers 153 have pressurized the top and bottom portions of the back yoke 151 and the permanent magnets 152. In this case, the rotor case 153 is manufactured by insert molding a bulk molding compound (BMC) as a complex raw material including a low shrinkage potassium-based material. The rotor case 153 does not only fix the back yoke 151 and the permanent magnets 152, but also takes charge of a sealing function for a coolant of the rotor 150.

As described above, the rotor 150 is formed to doubly fix the back yoke 151 and the permanent magnets 152 by the rotor covers 153 and the rotor case 154, to thereby prevent the permanent magnets 152 from seceding from the back yoke 151. Moreover, the rotor 150 has a heat generating characteristic according to rotation of the rotor 150, and may be continuously cooled by a coolant flowing in the rotor chamber RC.

In the above embodiment illustrated, the permanent-magnets 152 of a split piece structure have been used, but a number of N-pole and S-pole split magnetized ring-shaped permanent magnets may be also used.

The rotating assembly 160 is formed by an assembly of the rotor 150 and an impeller 162 with respect to the rotating shaft 161, in which the impeller 162 fixed to the rotating shaft 161 is rotated together due to the rotation of the rotor 150 opposite to the stator 140. Here, the central axis of the rotating shaft 161 becomes a basis of axial alignment with respect to the center of the stator 140 that is a fixed element and the centers of the rotor 150 and the impeller 162 that are rotating elements. In other words, the central axis of the rotating shaft 161 is the basis for preventing misalignment of the center axes of the fixed element and the rotating elements to thereby suppress vibration and noise that may occur at the time of operation of a water pump.

When the rotating assembly 160 is assembled with the rotor chamber RC in the pump body 110, first and second bearings 111 and 112 are combined to support and facilitate the rotation of the rotating shaft 161. Here, the first bearing 111 may be formed of a pair of semi-circular structures, and may be detachably coupled to the rotating shaft 161 at a state of completion of the rotating assembly 160, or may be formed of an ordinary circular structure and may be coupled to the rotating shaft 161 in advance before assembling the impeller 162 with the rotating shaft 161. In addition, the second bearing 112 may be pressingly fitted into the pump body 110 in a pair of semi-circular structure, or an ordinary circular structure, and then may be coupled to the rotating shaft 161 when the rotating assembly 160 is assembled in the rotor chamber RC of the pump body 110. In this case, mounting holes (not shown) into which the first and second bearings 111 and 112 are fitted may be formal on the outer circumferential surface of the rotating shaft 161.

For example, the impeller 162 is fixed to the rotating shaft 161 by an axial screw 163, and includes a plurality of wings with a downward slope outwardly from the central axis corresponding to bending regions of the pump cover 120. The impeller 162 takes charge of pressurizing a coolant introduced from the pump cover inlet 121 through high-speed rotation thereof, and discharging the introduced coolant via the pump cover outlet 122.

The driver 170 includes a connector 171 to which a connector pin 171 a is connected, and a printed circuit board (PCB) 172 in which a motor driving circuit is mounted. Here, the connector pin 171 a is extended in the inside of a connector housing that is formed integrally with the pump body 110, to thus configure the connector 171. In this case, the PCB 172 is electrically connected to an external power source through the connector pin 171 a, and receives a control signal applied from an external controller and a position signal from a Hall sensor, to thereby control operation of the water pump. Here, the PCB 172 is coupled in the pump body 110 through a screw coupling or a snap coupling.

A process for assembling the water pump will be briefly described below. First, the pump body 110 is formed by insert molding the stator 140 and the connector 171 in a single configuration and with a single material. Here, the rotating assembly 160 is formed into a complete body in which the rotor 150 and the impeller 162 are combined with the rotating shaft 161.

Then, the rotating assembly 160 is combined and assembled in the rotor chamber RC formed at the top of the pump body 110, together with the first and second bearings 111 and 112, and the pump cover 120 is coupled to the pump body 110 at a state where the rotating assembly 160 has been assembled in the rotor chamber RC of the pump body 110. In addition, the PCB 172 of the driver 170 is mounted in the driver chamber DC formed at the bottom of the pump body 110. The driver cover 130 is coupled to the pump body 110 at a state where the PCB 172 has been assembled in the driver chamber DC of the pump body 110.

Then, the finally completed water pump is directly combined to the engine block 180, to thus finalize an assembly of the water pump. Especially, when the water pump is coupled to the engine block 180, a third O-ring 117 is inserted between the pump cover 120 and the engine block 180, to thus guarantee sealing performance. In this case, the third O-ring 117 is inserted at a time of combining the pump cover 120 and the engine block 180, to thus form a space for closely adhering the pump cover 120 and the engine block 180. The engine block 180 is formed to have a stepped structure in correspondence to bending regions of the pump cover 120 (see FIG. 1A).

FIG. 2A is a cross-sectional view of a water pump employing a waterproof structure according to a modified embodiment of the first embodiment of the present invention. FIG. 2B is a plan view of a pump body in the water pump of FIG. 2A. FIG. 2A is a cross-sectional view taken along line B-B′ of FIG. 2B.

A water pump according to a modified embodiment of the first embodiment of the present invention is obtained by removing a pump cover 120 from the water pump according to the first embodiment of the present invention, in which a coolant path structure of the pump cover 120 is implemented in an engine block 280, to thus allow the engine block 280 to take charge of a function of the pump cover 120 in the water pump according to the first embodiment.

Specifically, similarly to the water pump according to the first embodiment, the water pump according to the modified embodiment of the first embodiment includes a pump body 210, a driver cover 230, a stator 240, a rotor 250, a rotating assembly 260, and a driver 270. In this case, the stator 240 includes a stator core 241, a bobbin 242, and a coil 243, and the rotor 250 includes a back yoke 251, permanent magnets 252, rotor covers 253, and a rotor case 254. In addition, the rotating assembly 260 includes the rotor 250, a rotating shaft 261, and an impeller 262, and the driver 270 includes a connector 271, a connector pin 271 a, and a PCB 272.

As described above, since major components of the water pump according to the modified embodiment of the first embodiment are same as those of the water pump according to the first embodiment, the detailed description thereof will be omitted but can be easily understood by those skilled in the art.

However, since the pump body 210 has a structure having no pump cover, no holes for coupling the pump cover are formed in the pump body 210. Accordingly, an O-ring 214 that corresponds to the first O-ring 114 is placed between the engine block 280 and the pump body 210.

In particular, the engine block 280 is formed to have a coolant path therein on behalf of the pump cover 120 of the water pump according to the first embodiment. In other words, like the pump cover 120 of the water pump according to the first embodiment, the engine block 280 guides a flow of the coolant from the engine to the radiator, and to this end, an engine block inlet 281 connected to the engine and an engine block outlet 282 connected to the radiator are formed in the engine block.

In addition, the engine block 280 is coupled with the pump body 210 using a screw or bolt 213 b, and a stud nut 213 c, to thus form a volute chamber VC that pressurizes a coolant by rotation of the impeller 262.

A process for assembling the water pump will be briefly described below. First, the rotating assembly 260 is combined and assembled in the rotor chamber RC formed on the top of the pump body 210, together with first and second bearings 211 and 212. In addition, the PCB 272 of the driver 270 is mounted in the driver chamber DC formed at the bottom Of the pump body 210. The driver cover 230 is coupled to the pump body 210 at a state where the PCB 272 has been assembled in the driver chamber DC of the pump body 210. Then, the finally completed water pump is directly combined to the engine block 280, to thus finalize an assembly of the water pump.

FIG. 3A is a cross-sectional view of a water pump employing a waterproof structure according to a second embodiment of the present invention. FIG. 3B is a plan view of a pump body in the water pump of FIG. 3A. FIG. 3A is a cross-sectional view taken along line C-C′ of FIG. 3B.

A water pump according to the second embodiment has a structure that a stator core 341 of a stator 340 is extended from the water pump according to the first embodiment, and is exposed to the outside of the pump body 310, in which a corresponding stator core 341 is coupled to the engine block 380 instead of the pump body 310.

Specifically, similarly to the water pump according to the first embodiment, the water pump according to the second embodiment includes a pump body 310, a pump cover 320, a driver cover 330, a stator 340, a rotor 350, a rotating assembly 360, and a driver 370. In this case, the stator 340 includes a stator core 341, a bobbin 342, and a coil 343, and the rotor 350 includes a back yoke 351, permanent magnets 352, rotor covers 353, and a rotor case 354. In addition, the rotating assembly 360 includes the rotor 350, a rotating shaft 361, and an impeller 362, and the driver 370 includes a connector 371, a connector pin 371 a, and a PCB 372. As described above, since major components of the water pump according to the second embodiment are same as those of the water pump according to the first embodiment, the detailed description thereof will be omitted but can be easily understood by those skilled in the art.

However, the stator 340 is molded to have the stator core 341 of a rectangular shape that is exposed to the outside of the pump body 310 and housed partially in the pump body 310. Accordingly, the stator core 341 is formed so that a portion whose portion is housed in the inside of the pump body 310 and combined with the bobbin 342 around which the coil 343 is wound, and a portion that is exposed to the outside of the pump body 310 and is coupled with the engine block 380, are integrally fabricated with each other.

For this purpose, the stator core 341 is formed to have a through-hole 341 a through which a molding material may be inserted into the inside of the pump body 310. Accordingly, even though the pump body 310 is exposed to the outside, the stator core 341 may be fixed to the pump body 310. Also, the stator core 341 is formed to have a coupling hole 341 b through which the stator core 341 may be coupled to the engine block 380 by a screw or bolt 313 b. In this ease, the stator core 341 is directly coupled to the engine block 380, using the screw or bolt 313 b, to thus dissipate heat generated from the coil 343 depending on the driving of the motor, as well as to achieve a strong coupling with the engine, and to take advantage of the direct coupling between the stator core 341 and the engine block 380 as the ground of the coil 343, to thereby discharge electromagnetic noise externally.

A process for assembling the water pump will be briefly described below. First, the rotating assembly 360 is combined and assembled in the rotor chamber RC formed on the top of the pump body 310, together with first and second bearings 311 and 312. In addition, the pump cover 320 is coupled to the pump body 310 at a state Where the rotating assembly 360 has been assembled in the rotor chamber RC of the pump body 310.

In addition, the PCB 372 of the driver 370 is mounted in the driver chamber DC formed at the bottom of the pump body 310. The driver cover 330 is coupled to the pump body 310 at a state where the PCB 372 has been assembled in the driver chamber DC of the pump body 310.

Then, the finally completed water pump is completely assembled in a manner that a coupler 313 b that penetrates the stator core 341 exposed to the outside is directly combined to the engine block 380.

FIG. 4A is a cross-sectional view of a water pump employing a waterproof structure according to a modified embodiment of the second embodiment of the present invention. FIG. 4B is a plan view of a pump body in the water pump of FIG. 4A. FIG. 4A is a cross-sectional view taken along line D-D′ of FIG. 4B.

A water pump according to the modified embodiment of the second embodiment of the present invention is obtained by removing a pump cover 320 from the water pump according to the second embodiment of the present invention, in which a coolant path structure of the pump cover 120 is implemented in an engine block 480, to thus allow the engine block 480 to take charge of a function of the pump cover 320 in the water pump according to the second embodiment.

Specifically, similarly to the water pump according to the second embodiment, the water pump according to the modified embodiment of the second embodiment includes a pump body 410, a driver cover 430, a stator 440, a rotor 450, a rotating assembly 460, and a driver 470. In this case, the stator 440 includes a stator core 441, a bobbin 442, and a coil 443, and the rotor 450 includes a back yoke 451, permanent magnets 452, rotor covers 453, and a rotor case 454. in addition, the rotating assembly 460 includes the rotor 450, a rotating shaft 461, and an impeller 462, and the driver 470 includes a connector 471, a connector pin 471 a, and a PCB 472. As described above, since major components of the water pump according to the modified embodiment of the second embodiment are same as those of the water pump according to the second embodiment, the detailed description thereof will be omitted but can be easily understood by those skilled in the art.

However, since the pump body 410 has a structure having no pump cover 320 of FIG. 3A, no holes for coupling the pump cover are formed in the pump body 410.

In particular, the engine block 480 is formed to have a coolant path therein on behalf of the pump cover 320 of FIG. 3A, In other words, like the pump cover 320 of FIG. 3A, the engine block 480 guides a flow of the coolant from the engine to the radiator, and to this end, an engine block inlet 481 connected to the engine and an engine block outlet 482 connected to the radiator are formed in the engine block.

In addition, the engine block 480 is coupled with the pump body 410, to thus form a volute chamber VC that pressurizes a coolant by rotation of the impeller 462.

As shown in FIGS. 3A and 38, the stator 440 is molded to have the stator core 441 that is exposed to the outside of the pump body 410 and housed partially in the pump body 410, Accordingly, the stator core 441 is formed so that a portion whose portion is housed in the inside of the pump body 410 and combined with the bobbin 442 around which the coil 443 is wound, and a portion that is exposed to the outside of the pump body 410 and is coupled with the engine block 480, are integrally fabricated with each other.

Here, the stator core 441 may be formed in a rectangular shape as shown in FIGS. 3A and 38, but the stator core 441 may be formed in a rectangular structure in which outer circumferential grooves 441 a are formed in the stator core 441 and a molding material for the pump body 410 is inserted into the outer circumferential grooves 441 a. In other words, the stator core 441 is formed so that the molding material for the pump body 410 may be filled in the inserted into the outer circumferential grooves 441 a. Accordingly, even though the pump body 410 is exposed to the outside, the stator core 441 may be fixed to the pump body 410. Also, the stator core 441 is formed to have a coupling hole 441 b through which the stator core 441 may be coupled to the engine block 480 by a screw or bolt 413 b.

A process for assembling the water pump will be briefly described below. First, the rotating assembly 460 is combined and assembled in the rotor chamber RC formed on the top of the pump body 410, together with first and second bearings 411 and 412. In addition, the PCB 472 of the driver 470 is mounted in the driver chamber DC formed at the bottom of the pump body 410. The driver cover 430 is coupled to the pump body 410 at a state where the PCB 472 has been assembled in the driver chamber DC of the pump body 410. Then, the finally completed water pump is completely assembled in a manner that a coupler 413 b that penetrates the stator core 441 exposed to the outside is directly combined to the engine block 480.

In the second embodiment and the modified embodiment of the second embodiment that are shown in FIGS. 3A to 4B, respectively, the upper portions of the pump bodies 310 and 410 are inserted and mounted in the inside of the engine blocks 380 and 480, respectively, to thereby implement a water pump of a compact structure as a whole. In addition, even in the first embodiment and the modified embodiment of the first embodiment, it is possible to vary a water pump into a structure that the upper portions of the pump bodies 110 and 210 are inserted and mounted in the inside of the volute chambers VC formed in the engine blocks 180 and 280, respectively, so that the exposed length of the pump motor can be shortened, similarly to the second embodiment.

In the above-described embodiments, the cases where the water pump has been integrally combined with the engine block have been described, but it is possible to use the water pump separated from the engine block or integrally combined with the radiator.

As described above, the present invention has been described with respect to particularly preferred embodiments. However, the present invention is not limited to the above embodiments, and it is possible for one who has an ordinary skill in the art to make various modifications and variations, without departing off the spirit of the present invention. Thus, the protective scope of the present invention is not defined within the detailed description thereof but is defined by the claims to be described later and the technical spirit of the present invention.

INDUSTRIAL APPLICABILITY

The present invention can be applied for an automotive water pump in which regions of a rotor chamber and a driver chamber are formed and a stator and a connector are implemented into an integral pump body by an insert molding method, to thus enhance a waterproof performance of the water pump and enhance an assembly through simplification of an assembly structure. 

1. An automotive water pump comprising: a pump body in which a stator and a connector are molded in an integral structure, and a space for a rotor chamber and a space for a driver chamber are provided on top and bottom portions of the pump body, respectively; a rotating assembly that is accommodated and combined in the rotor chamber, and that pressurizes and discharges a coolant that flows in from the outside by rotation of an impeller that is combined on top of a rotating axis according to rotation of the rotating axis to which a rotor is fixed; and a driver cover that covers the driver chamber.
 2. The automotive water pump according to claim 1, further comprising a pump cover that comprises a volute chamber that is directly coupled to the pump body to thus guide a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.
 3. The automotive water pump according to claim 2, wherein the pump cover is inserted into the inside of an engine block.
 4. The automotive water pump according to claim 3, wherein the engine block comprises the volute chamber that is directly coupled to the pump body to thus guide a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.
 5. The automotive water pump according to claim 1, wherein the pump body is molded by using a single material of polyphenylene sulfide (PPS) or bulk molding compound (BMC), with an insert molding method.
 6. The automotive water pump according to claim 5, wherein the rotor primarily fixes a back yoke and a permanent magnet by a rotor cover, and then secondarily surrounds and fixes the back yoke and an outer circumferential surface of the back yoke by insert molding the BMC.
 7. The automotive water pump according to claim 5, wherein bearings are inserted into and combined with top and bottom portions of the rotating assembly when the rotating assembly are coupled with the rotor chamber.
 8. The automotive water pump according to claim 1, wherein the stator comprises a stator core and a portion of the stator core is exposed to the outside of the pump body.
 9. The automotive water pump according to claim 8, wherein the stator core comprises a fastening hole passing through a portion of the stator core exposed to the outside of the pump body; to thus be coupled directly to the engine block.
 10. The automotive water pump according to claim 9, wherein the engine block comprises the volute chamber that guides a flow of the coolant, and that pressurizes the coolant by rotation of the impeller.
 11. The automotive water pump according to claim 8, wherein the stator core comprises through-holes or outer circumferential grooves into which a molding material of polyphenylene sulfide (PPS) or bulk molding compound (BMC) is filled at the time of performing an insert molding method, to then be fixed to the pump body. 